Pay-per-call API platform on Base (USDC) offering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that provides a broad catalog of pay-per-request endpoints across four categories: Data & Analytics (metrics, reports, data export, insights), AI & Machine Learning (sentiment analysis, text summarization, classification, embeddings), Finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and Infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are priced at $0.02 per request, payable in USDC on the Base network via the x402 protocol.
The specific endpoint `/api/v1/keys/27` is listed as "Premium API Access" and carries a max amount of 20,000 base units of USDC (0.02 USD, i.e., two cents). Payment is settled on-chain to address 0x1A2B...85F3 using USDC (contract 0x8335...2913) on Base. The platform advertises no API keys, no rate limits, no minimums, and instant access — users simply attach an x402 payment header to each request.
Documentation is minimal: the /api, /pricing, and /README pages all resolve to a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema documentation, and no usage examples available from the crawled pages. The exact functionality behind the "Premium API Access" label at `/api/v1/keys/27` is unclear — it may be a meta-endpoint for obtaining access keys or a generic premium tier, but this cannot be confirmed from available material.
Capabilities
Use cases
- —Agents needing on-demand AI inference (sentiment, summarization, classification, embeddings) without API key management
- —Fetching real-time crypto prices, gas estimates, or exchange rates with per-call payment
- —Geocoding or data validation as a utility service with no subscription commitment
- —Exporting analytics data or generating insights on a pay-as-you-go basis
Fit
Best for
- —AI agents that need keyless, pay-per-call access to diverse utility endpoints
- —Developers prototyping with low-cost, no-commitment API access on Base
- —Web3-native applications that prefer on-chain USDC settlement over traditional billing
Not for
- —High-volume production workloads where per-call crypto payment overhead is impractical
- —Users who need detailed API documentation, SLAs, or guaranteed uptime commitments
- —Teams without USDC on Base or unfamiliar with x402 payment flows
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/keys/27 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no OpenAPI spec, no request/response schema, no documentation beyond a landing page listing, and the specific purpose of /api/v1/keys/27 ('Premium API Access') is ambiguous. Effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available for any endpoint
- —The /api, /pricing, and /README pages return only a 'Connect wallet' prompt with no useful content
- —The exact functionality of /api/v1/keys/27 ('Premium API Access') is unclear — it may be a meta-endpoint rather than a data API
- —No request or response examples are available anywhere in the crawled material
Citations
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The x402 challenge for /api/v1/keys/27 specifies maxAmountRequired of 20000 base units of USDC (0.02 USD) on Basehttps://lowpaymentfee.com/api/v1/keys/27
- —Available API categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/keys/27